237 research outputs found
The effect of phosphodiesterase-5 inhibitors on cerebral blood flow in humans: A systematic review.
Agents that augment cerebral blood flow (CBF) could be potential treatments for vascular cognitive impairment. Phosphodiesterase-5 inhibitors are vasodilating drugs established in the treatment of erectile dysfunction (ED) and pulmonary hypertension. We reviewed published data on the effects of phosphodiesterase-5 inhibitors on CBF in adult humans. A systematic review according to PRISMA guidelines was performed. Embase, Medline and Cochrane Library Trials databases were searched. Sixteen studies with 353 participants in total were retrieved. Studies included healthy volunteers and patients with migraine, ED, type 2 diabetes, stroke, pulmonary hypertension, Becker muscular dystrophy and subarachnoid haemorrhage. Most studies used middle cerebral artery flow velocity to estimate CBF. Few studies employed direct measurements of tissue perfusion. Resting CBF velocity was unaffected by phosphodiesterase-5 inhibitors, but cerebrovascular regulation was improved in ED, pulmonary hypertension, diabetes, Becker's and a group of healthy volunteers. This evidence suggests that phosphodiesterase-5 inhibitors improve responsiveness of the cerebral vasculature, particularly in disease states associated with an impaired endothelial dilatory response. This supports the potential therapeutic use of phosphodiesterase-5 inhibitors in vascular cognitive impairment where CBF is reduced. Further studies with better resolution of deep CBF are warranted. The review is registered on the PROSPERO database (registration number CRD42016029668)
Correlates of comorbid anxiety and externalizing disorders in childhood obsessive compulsive disorder
The present study examines the influence of diagnostic comorbidity on the demographic, psychiatric, and functional status of youth with a primary diagnosis of obsessive compulsive disorder (OCD). Two hundred and fifteen children (ages 5–17) referred to a university-based OCD specialty clinic were compared based on DSM-IV diagnostic profile: OCD without comorbid anxiety or externalizing disorder, OCD plus anxiety disorder, and OCD plus externalizing disorder. No age or gender differences were found across groups. Higher OCD severity was found for the OCD + ANX group, while the OCD + EXT group reported greater functional impairment than the other two groups. Lower family cohesion was reported by the OCD + EXT group compared to the OCD group and the OCD + ANX group reported higher family conflict compared to the OCD + EXT group. The OCD + ANX group had significantly lower rates of tic disorders while rates of depressive disorders did not differ among the three groups. The presence of comorbid anxiety and externalizing psychopathology are associated with greater symptom severity and functional and family impairment and underscores the importance of a better understanding of the relationship of OCD characteristics and associated disorders. Results and clinical implications are further discussed
Radio & Optical Interferometry: Basic Observing Techniques and Data Analysis
Astronomers usually need the highest angular resolution possible, but the
blurring effect of diffraction imposes a fundamental limit on the image quality
from any single telescope. Interferometry allows light collected at
widely-separated telescopes to be combined in order to synthesize an aperture
much larger than an individual telescope thereby improving angular resolution
by orders of magnitude. Radio and millimeter wave astronomers depend on
interferometry to achieve image quality on par with conventional visible and
infrared telescopes. Interferometers at visible and infrared wavelengths extend
angular resolution below the milli-arcsecond level to open up unique research
areas in imaging stellar surfaces and circumstellar environments.
In this chapter the basic principles of interferometry are reviewed with an
emphasis on the common features for radio and optical observing. While many
techniques are common to interferometers of all wavelengths, crucial
differences are identified that will help new practitioners avoid unnecessary
confusion and common pitfalls. Concepts essential for writing observing
proposals and for planning observations are described, depending on the science
wavelength, angular resolution, and field of view required. Atmospheric and
ionospheric turbulence degrades the longest-baseline observations by
significantly reducing the stability of interference fringes. Such
instabilities represent a persistent challenge, and the basic techniques of
phase-referencing and phase closure have been developed to deal with them.
Synthesis imaging with large observing datasets has become a routine and
straightforward process at radio observatories, but remains challenging for
optical facilities. In this context the commonly-used image reconstruction
algorithms CLEAN and MEM are presented. Lastly, a concise overview of current
facilities is included as an appendix.Comment: 45 pages, 14 Figures; an abridged version of a chapter to appear in
Volume 2 of Planets, Stars and Stellar Systems, to be published in 2011 by
Springe
Evidence-Based Assessment of Child Obsessive Compulsive Disorder: Recommendations for Clinical Practice and Treatment Research
Obsessive-compulsive disorder (OCD) presents heterogeneously and can be difficult to assess in youth. This review focuses on research-supported assessment approaches for OCD in childhood. Content areas include pre-visit screening, diagnostic establishment, differential diagnosis, assessment of comorbid psychiatric conditions, tracking symptom severity, determining psychosocial functioning, and evaluating clinical improvement. Throughout this review, similarities and differences between assessment approaches geared towards clinical and research settings are discussed
A systematic review of outcome and outcome-measure reporting in randomised trials evaluating surgical interventions for anterior-compartment vaginal prolapse: a call to action to develop a core outcome set
INTRODUCTION: We assessed outcome and outcome-measure reporting in randomised controlled trials evaluating surgical interventions for anterior-compartment vaginal prolapse and explored the relationships between outcome reporting quality with journal impact factor, year of publication, and methodological quality. METHODS: We searched the bibliographical databases from inception to October 2017. Two researchers independently selected studies and assessed study characteristics, methodological quality (Jadad criteria; range 1-5), and outcome reporting quality Management of Otitis Media with Effusion in Cleft Palate (MOMENT) criteria; range 1-6], and extracted relevant data. We used a multivariate linear regression to assess associations between outcome reporting quality and other variables. RESULTS: Eighty publications reporting data from 10,924 participants were included. Seventeen different surgical interventions were evaluated. One hundred different outcomes and 112 outcome measures were reported. Outcomes were inconsistently reported across trials; for example, 43 trials reported anatomical treatment success rates (12 outcome measures), 25 trials reported quality of life (15 outcome measures) and eight trials reported postoperative pain (seven outcome measures). Multivariate linear regression demonstrated a relationship between outcome reporting quality with methodological quality (β = 0.412; P = 0.018). No relationship was demonstrated between outcome reporting quality with impact factor (β = 0.078; P = 0.306), year of publication (β = 0.149; P = 0.295), study size (β = 0.008; P = 0.961) and commercial funding (β = -0.013; P = 0.918). CONCLUSIONS: Anterior-compartment vaginal prolapse trials report many different outcomes and outcome measures and often neglect to report important safety outcomes. Developing, disseminating and implementing a core outcome set will help address these issues
Alpine Crossroads or Origin of Genetic Diversity? Comparative Phylogeography of Two Sympatric Microgastropod Species
The Alpine Region, constituting the Alps and the Dinaric Alps, has played a major role in the formation of current patterns of biodiversity either as a contact zone of postglacial expanding lineages or as the origin of genetic diversity. In our study, we tested these hypotheses for two widespread, sympatric microgastropod taxa – Carychium minimum O.F. Müller, 1774 and Carychium tridentatum (Risso, 1826) (Gastropoda, Eupulmonata, Carychiidae) – by using COI sequence data and species potential distribution models analyzed in a statistical phylogeographical framework. Additionally, we examined disjunct transatlantic populations of those taxa from the Azores and North America. In general, both Carychium taxa demonstrate a genetic structure composed of several differentiated haplotype lineages most likely resulting from allopatric diversification in isolated refugial areas during the Pleistocene glacial periods. However, the genetic structure of Carychium minimum is more pronounced, which can be attributed to ecological constraints relating to habitat proximity to permanent bodies of water. For most of the Carychium lineages, the broader Alpine Region was identified as the likely origin of genetic diversity. Several lineages are endemic to the broader Alpine Region whereas a single lineage per species underwent a postglacial expansion to (re)colonize previously unsuitable habitats, e.g. in Northern Europe. The source populations of those expanding lineages can be traced back to the Eastern and Western Alps. Consequently, we identify the Alpine Region as a significant ‘hot-spot’ for the formation of genetic diversity within European Carychium lineages. Passive dispersal via anthropogenic means best explains the presence of transatlantic European Carychium populations on the Azores and in North America. We conclude that passive (anthropogenic) transport could mislead the interpretation of observed phylogeographical patterns in general
Cluster Analysis of the Yale Global Tic Severity Scale (YGTSS): Symptom Dimensions and Clinical Correlates in an Outpatient Youth Sample
Search for strongly interacting massive particles generating trackless jets in proton-proton collisions at s = 13 TeV
A search for dark matter in the form of strongly interacting massive particles (SIMPs) using the CMS detector at the LHC is presented. The SIMPs would be produced in pairs that manifest themselves as pairs of jets without tracks. The energy fraction of jets carried by charged particles is used as a key discriminator to suppress efficiently the large multijet background, and the remaining background is estimated directly from data. The search is performed using proton-proton collision data corresponding to an integrated luminosity of 16.1 fb - 1 , collected with the CMS detector in 2016. No significant excess of events is observed above the expected background. For the simplified dark matter model under consideration, SIMPs with masses up to 100 GeV are excluded and further sensitivity is explored towards higher masses
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